Suppose these data show the number of gallons of gasoline sold by a gasoline distributor in Bennington, Vermont, over the past 12 weeks.

Week	Sales (1,000s of gallons)
1	18
2	21
3	19
4	24
5	18
6	17
7	21
8	19
9	23
10	21
11	15
12	23

(a)

Compute four-week and five-week moving averages for the time series.

Week	Time Series Value	4-Week Moving Average Forecast	5-Week Moving Average Forecast
1	18
2	21
3	19
4	24
5	18
6	17
7	21
8	19
9	23
10	21
11	15
12	23

(b)

Compute the MSE for the four-week moving average forecasts. (Round your answer to two decimal places.)

Compute the MSE for the five-week moving average forecasts. (Round your answer to two decimal places.)

(c)

What appears to be the best number of weeks of past data (three, four, or five) to use in the moving average computation? MSE for the three-week moving average is 12.11.

Three weeks appears to be best, because the three-week moving average provides the smallest MSE.Three weeks appears to be best, because the three-week moving average provides the largest MSE. Four weeks appears to be best, because the four-week moving average provides the smallest MSE.Five weeks appears to be best, because the five-week moving average provides the smallest MSE.None appear better than the others, because they all provide the same MSE.

a) Compute four-week and five-week moving averages for the time serics (a) Compute fouf-whek and five-week mowina averaaes for the time series (b) Compute the M5E for the four-neek moving wereje forecasts. (Rouna your antwer to heo dedimal placec) Compute the Maf for the fie-weck moriag average forecasts. (Round your answer to tos decimal places.) (c) What apsears to be the best number of weeks of sast date (three, four, or five) te use in the movieg average coinpucatient Mace for tie three wack moring average is 12 t1. Three weeks appears ta be best, because the three-week moving average provises the onaleat rse. Throe weeks appears to be best, becauge the thete- neck moving average proviges the largent Mat. Four weeks appears to be best, becajse the four-meki moving average provides the shallat MSt. Flue weeks appears to be ben, becalase the five-weck mority averepe provides the smallet MSt. None appear better than the ethers, because they all provide the same MSt